The tools available for thought control in early modern Europe were poor even by 20th century standards, but they worked. And for hundreds of years, the struggle primarily centered around that increasingly important first mass manufactured article in Western culture: the book. Whether you could print them, possess them, traffic in them, read them, teach from them without the permission or control of an entity empowered to punish thought.
By the end of the 17th century censorship of written material in Europe had begun to break down first in the Netherlands then in the UK then afterwards in waves throughout the European world and the book became an article of subversive commerce and began eating away at the control of thought.
By the late 18th century that struggle for the freedom of reading had begun to attack the substance of Christianity itself and the European world trembled on the brink of the first great revolution of the mind. It spoke of “liberté, égalité, fraternité”, but actually it meant freedom to think differently." -- https://archive.org/details/EbenMoglenRepublica2012